Dodgy CL results-- Advice?

[Nanno]

I got my CAE/CL results back from WADDL today, and everyone's tests came back negative for everything (yay!) except Lilly's CL test. She came back with a positive result and a titer of 1:64. However, the note on the paper says,

"Titers of < 1:8 are considered negative. The predictive value of negative titers is enhanced if all herd mates also test negative. Titers between 1:8 and 1:256 are interpreted as evidence of infection, colostral immunity, or vaccination."

I'm quite sure Lilly has never been vaccinated for CL, and if she had then I imagine her past tests would have come back positive. I'm not sure about colostral immunity. She was dam-raised for the first couple weeks after she was born. But once again, her tests have come back negative the last two years. If Lilly had antibodies from her mother, is it possible they wouldn't show up in her blood until now?

If Lilly somehow got infected, is it possible for her to infect my other goats if she has no clinical signs at all? She's never had an abscess and has never had a cough. Is there any way results could have been skewed by factors other than CL? Should I get her tested again, perhaps by a different lab? Since she's technically still considered negative, is there any reason for me to be concerned at all?

I'd appreciate any thoughts or advice.

[Dave-Trinity-Farms]

CL tests in general are kinda iffy. The best way is to test the puss, but of course by then you most likely know anyways. I am unsure how long it takes CL titers to build up to a point they can be tested for but I am guessing it can very from goat to goat. Ive know of positive goats that never popped an abscess, others that only popped one. For those other then the scar on a common CL location, you would never know. Do the retest in a month. Testing at WADDL again is offered for free and is ok to do so. WADDL is the best IMO.

Now for the most part a freshly infected goat is safe in terms of not having internal abscesses. So until you retest I wouldnt worry to much. BUT if she has babies she can not feed those babies until you know for sure. CL can pass through the milk. Usually takes abscess in the udder to make this happen, but with CL its always best to be safe then sorry. CL can be transferred as easily as using an outside buck that has breed a CL doe and then breeds yours. Its not the act of breeding you have to worry about but what the buck comes in contact with. Exampl, a positive doe pops an abscess or is in a pen with a goat that does. The puss gets onto the doe. The doe is bred to a buck. The buck now has it on him. He breeds your doe. Now your doe has it on her. CL is easily spread through direct contact from goat to goat to goat.

[Taffy]

This topic was discussed in one of the CE classes I took today. As Dave said, the CL test is very iffy unless you test the puss. Re-test Lily at least 2 more times and watch her for any clinical signs in the lymph node areas where CL shows up. When is she due?

[Nanno]

Thanks guys. Lilly actually is not due at all this year. She hated the young buck we tried to use and ended up not getting pregnant even though the buck owner said she held Lilly still for her guy. I'm not sure the buck liked Lilly either after she beat him up.

I'll wait a month and get her tested again. What if the number never changes? Is it possible she has CL immunity that may not have shown up until now? If she got CL, I'm not sure where she could have gotten it. The buck we bred her to is negative. Lilly did go down to visit my neighbor's Boers last fall when she came into heat, but that was months ago. How long could CL incubate, and how long might it take for the titer to reach a positive result?

I'll certainly keep an eye on her for any lumps or coughing.

[Dave-Trinity-Farms]

Can take CL over a year to show up. But because the CL is walled off in abscesses, its just hard to predict how long. I mean they still dont know for sure how long it stays active on surfaces. Some say a year, other say 2. I read one report that said 10 years but I think that was an extremist opinion.

[Nanno]

So I've been giving some thought to Lilly's CL test result, and of course I'm planning to send WADDL another sample as soon as I can get more blood draw tubes. If she does indeed test positive I'm going to guess that she almost certainly picked up the infection from my neighbor's Boers and I'm wondering if it might be in my best interest to start vaccinating for CL. However, I've read that the vaccine is only 80-85% effective, and of course it would mean that all my goats would forever test positive for CL even though they wouldn't have it.

On the other hand, even if Lilly ends up being negative I do wonder if it's still just a matter of time. Those Boers spend all summer going up and down the road past our house, which is the same one Phil and I take our goats walking on nearly every day. We also share a fence line at the back of our property. My goats don't often go that far afield, but I can't say it never happens. Also, there have been a couple of incidents where either their goats or mine escaped entirely and ended up on the other's property and even mingling together. In fact, my neighbor's herd dog once rounded up my goats off our property and put them with his herd, thinking they were his! Having a foolproof system that guarantees complete separation at all times simply isn't practical or financially feasible right now. I don't want to keep my goats penned all the time. I have 40 acres of prime goat browse and I can't afford not to use it, nor can I afford to "goat proof" the whole thing. For one thing, I'd have to build double fences along two sides.

So... with that in mind, do ya'll think it might be a good idea to vaccinate? I would of course have to make it very clear to any future goat buyers that my goats will test positive for the disease. In order for me to maintain a CL free herd without vaccinating, I'd have to be testing constantly, and I'm not sure I can afford that either. Vaccinating is a much cheaper option than twice-a-year blood tests and I wonder if it would be worth it just for the peace of mind to know that my critters are (mostly) protected from the ones next door. What do ya'll think?

[Taffy]

I would not vaccinate. Lilly is the only one who came up positive and even then the test wasn't conclusive. Do you know for a fact the Boer herd has CL? Have you seen abscesses on the goats or talked to the owner? I wouldn't do anything until Lilly was tested two more times 30 days apart.

Per WSU: An individual animal positive CL serology test does not necessarily mean an animal is infected with C. pseudotuberculosis or has CL (serology can also detect past, resolved infections).

Nan, I'm sure you have read this information from WSU but I will post it for everyone.

http://waddl.vetmed.wsu.edu/animal-disea...phadenitis

[Nanno]

I don't know for a fact that my neighbor's herd has CL (haven't personally seen abscesses), but I would be shocked if it wasn't in their herd. They're range goats, so it's hard to get up close enough for personal inspections. I know my neighbors buy a lot of cheap dairy culls and sale barn animals of unknown origin. They always have 300-500 goats at any given time. They did buy their current herd two years ago as one big group and the person they bought them from said it was a "closed herd" with no diseases. However, the goat herd they had before that was not so reputable, and since CL lives in the soil for a year or more, and given their living conditions, I'm sure the new herd has by now even if they were clean when they arrived.

When not out on their daily grazing rounds, the goats are kept in a small pasture which was eaten down to bare dirt years ago. When the neighbor's dog rounded up my goats and put them with his herd, my goats ended up going into that filthy place and came back up to their knees in cesspool muck. Of course, I washed all of them down with bleach water the moment I got them home, but that's the best I could do.

I know Lilly isn't shedding CL (and even if she continually tests positive she may never--who knows), but I do wonder if I'm going to end up eventually getting full-blown infectious cases because of what lives next door. This test result has really made me think about this issue for the first time and I have to admit it has me a bit concerned.

[Dave-Trinity-Farms]

Ya thats a tough spot to be in. The crap thing is, it could be all over their place and animals with no outward evidence of it. At great cost to you, you could put up another fence along that property 5 or 10 feet inward to give a lane so they cant touch. But if the wind blows from that direction to bring the infected dirt over to your side, or their dog comes over to your goats or even your dog after being in an infected area...

[Nanno]

It's not just a matter of putting up a second fence along that property--I'd actually have to put a double fence around two sides: their side and the road side. Since our property is triangle-shaped and those are our two longest sides, this presents a financial impossibility. I'd also have to quit walking our goats on Clennin road, which is where we take them nearly every day. The Boer herd also travels this road for most of the year, so my goats and theirs are already sharing the same turf and nibbling on the same roadside brush and weeds as they go along. I'd never given much thought to CL before, but now that I have I'm wondering if it's just a matter of time before I start dealing with clinical cases. I can't keep my goats in a glass bubble.

I don't want to make it sound like my neighbor is irresponsible. He has goats for a specific purpose, which is to mow down brush on his ranch. This means the goats roam all over the roadway and countryside surrounding (and sometimes on) my property. He was here first, and I admire his attempt to clear the land in the most environmentally responsible way possible. He tried using a giant brush hog and started a forest fire two years ago which is why he got back into goats. I fully understand why it would be impossible for him to test a herd that size and keep it clean. From his point of view, CL is nothing more than a minor inconvenience since most goats don't die from it.

The realization that my goats are almost certainly coming in contact with contaminated soil and forage is what prompted me to consider vaccinating. If the vaccine were more effective, I doubt I would think twice. But 80-85% isn't impressing me much so I do wonder if it's worth it. On the other hand, while my goats are probably coming in contact with CL, it's not like they're wallowing in it all the time. I wonder if vaccinating would boost their immune systems enough to prevent problems in this situation.

Other than the dodgy effectiveness and not being able to test for CL again, are there any other down sides to vaccinating? Do ya'll know anyone who does it? I wonder if I should also put this question to the folks over at TheGoatSpot. Maybe some of them have faced the same dilemma.